Problem solved. Recent photos posted on Facebook indicate that the plane went down in the stretch of water between the rubble mound connecting the oil tanks in the mud flats area to the coal wharf and the causeway, so actually on the harbour side opposite the end of the Khormaksar Airfield. Sadly my memory of the sight had it misplaced.
Hi David, I was an air traffic control officer at RAF Khormaksar 1963-65. I was on duty in the visual control room when said aircraft ditched in the harbour. It was definately on the harbour side of the causeway and ironically within an area depicted on some maps/charts as the "seaplane alighting area"! The aircraft was recovered and I have a photograph of it back on land shared by the RAF Marine Craft Unit base and the Khormaksar Sailing Club. XP 413 was repaired and later re-entered service operating from RAF Cottesmore, Rutland with, I think, 205 Sqn. BRgds, Jerry